So I'm working with a former NASA engineer on developing a header for my car...really smart guy who has been working on cars for a very long time. He's been designing his own exhausts and headers for over 40 years based on formulas from who knows where. All I know is the man is a miracle worker and every car he's ever worked on has made unbelievable power and torque after what he did.

Anyway, I need the exhaust cam specs for my motor and wanted to know if these numbers I found were correct. Any information is appreciated! Thanks ahead of time guys.

Bore: 83mm
Stroke: 85mm
Exhaust Cam Specs
Duration: 250* @ .003"
Opening: 56* BBDC
Closing: 14* ATDC
Lobe Height: 44.600mm (1.7560")
Base Circle: 35.941mm (1.415")
Lift: 8.6614mm (.341")
Valve Overlap: 19*

 

:sigh: i meant BP-Z3 not ZE.......

Anyway, im pretty sure i found the proper specs in the rules for Spec Miata

 

ive seen 2 conflicting sources....

http://www.solomiata.com/cams.html

vs

http://www.nasaproracing.com/rules/spec_miata_rules.pdf

 

Hmmmm

I suspect that Spec Miata rules are the correct set of numbers. The spec miata rules are super strict

 

I tend to agree. Also some of the valve timing values don't really match up quite right with the duration from the solomiata site. check out this thread

https://www.miataturbo.net/engine-performance-56/exhintake-mod-nb-head-63166/